[PATCH v2 05/24] drivers: hv: dxgkrnl: Creation of dxgcontext objects

[Iouri Tarassov]

Implement ioctls for dxgcontext creation/destruction:
   LX_DXCREATECONTEXTVIRTUAL(D3DKMTCreateContextVirtual),
   LX_DXDESTROYCONTEXT(D3DKMTDestroyContext)

A dxgcontext object represents a GPU execution thread. GPU DMA
buffers and synchronization operations are submitted for execution
to a GPU context. GPU contexts belong to a dxgdevice object.

Signed-off-by: Iouri Tarassov <iourit@xxxxxxxxxxxxxxxxxxx>
---
 drivers/hv/dxgkrnl/dxgadapter.c | 102 +++++++++++++++++++
 drivers/hv/dxgkrnl/dxgkrnl.h    |  38 +++++++
 drivers/hv/dxgkrnl/dxgprocess.c |   4 +
 drivers/hv/dxgkrnl/dxgvmbus.c   |  99 ++++++++++++++++++
 drivers/hv/dxgkrnl/ioctl.c      | 172 ++++++++++++++++++++++++++++++++
 drivers/hv/dxgkrnl/misc.h       |   1 +
 6 files changed, 416 insertions(+)

diff --git a/drivers/hv/dxgkrnl/dxgadapter.c b/drivers/hv/dxgkrnl/dxgadapter.c
index c7e1dc55de49..9cdc81d4db4a 100644
--- a/drivers/hv/dxgkrnl/dxgadapter.c
+++ b/drivers/hv/dxgkrnl/dxgadapter.c
@@ -210,7 +210,9 @@ struct dxgdevice *dxgdevice_create(struct dxgadapter *adapter,
 		device->adapter = adapter;
 		device->process = process;
 		kref_get(&adapter->adapter_kref);
+		INIT_LIST_HEAD(&device->context_list_head);
 		init_rwsem(&device->device_lock);
+		init_rwsem(&device->context_list_lock);
 		INIT_LIST_HEAD(&device->pqueue_list_head);
 		device->object_state = DXGOBJECTSTATE_CREATED;
 		device->execution_state = _D3DKMT_DEVICEEXECUTION_ACTIVE;
@@ -252,6 +254,20 @@ void dxgdevice_destroy(struct dxgdevice *device)
 
 	dxgdevice_stop(device);
 
+	{
+		struct dxgcontext *context;
+		struct dxgcontext *tmp;
+
+		pr_debug("destroying contexts\n");
+		dxgdevice_acquire_context_list_lock(device);
+		list_for_each_entry_safe(context, tmp,
+					 &device->context_list_head,
+					 context_list_entry) {
+			dxgcontext_destroy(process, context);
+		}
+		dxgdevice_release_context_list_lock(device);
+	}
+
 	/* Guest handles need to be released before the host handles */
 	hmgrtable_lock(&process->handle_table, DXGLOCK_EXCL);
 	if (device->handle_valid) {
@@ -305,6 +321,32 @@ bool dxgdevice_is_active(struct dxgdevice *device)
 	return device->object_state == DXGOBJECTSTATE_ACTIVE;
 }
 
+void dxgdevice_acquire_context_list_lock(struct dxgdevice *device)
+{
+	down_write(&device->context_list_lock);
+}
+
+void dxgdevice_release_context_list_lock(struct dxgdevice *device)
+{
+	up_write(&device->context_list_lock);
+}
+
+void dxgdevice_add_context(struct dxgdevice *device, struct dxgcontext *context)
+{
+	down_write(&device->context_list_lock);
+	list_add_tail(&context->context_list_entry, &device->context_list_head);
+	up_write(&device->context_list_lock);
+}
+
+void dxgdevice_remove_context(struct dxgdevice *device,
+			      struct dxgcontext *context)
+{
+	if (context->context_list_entry.next) {
+		list_del(&context->context_list_entry);
+		context->context_list_entry.next = NULL;
+	}
+}
+
 void dxgdevice_release(struct kref *refcount)
 {
 	struct dxgdevice *device;
@@ -313,6 +355,66 @@ void dxgdevice_release(struct kref *refcount)
 	vfree(device);
 }
 
+struct dxgcontext *dxgcontext_create(struct dxgdevice *device)
+{
+	struct dxgcontext *context = vzalloc(sizeof(struct dxgcontext));
+
+	if (context) {
+		kref_init(&context->context_kref);
+		context->device = device;
+		context->process = device->process;
+		context->device_handle = device->handle;
+		kref_get(&device->device_kref);
+		INIT_LIST_HEAD(&context->hwqueue_list_head);
+		init_rwsem(&context->hwqueue_list_lock);
+		dxgdevice_add_context(device, context);
+		context->object_state = DXGOBJECTSTATE_ACTIVE;
+	}
+	return context;
+}
+
+/*
+ * Called when the device context list lock is held
+ */
+void dxgcontext_destroy(struct dxgprocess *process, struct dxgcontext *context)
+{
+	pr_debug("%s %p\n", __func__, context);
+	context->object_state = DXGOBJECTSTATE_DESTROYED;
+	if (context->device) {
+		if (context->handle.v) {
+			hmgrtable_free_handle_safe(&process->handle_table,
+						   HMGRENTRY_TYPE_DXGCONTEXT,
+						   context->handle);
+		}
+		dxgdevice_remove_context(context->device, context);
+		kref_put(&context->device->device_kref, dxgdevice_release);
+	}
+	kref_put(&context->context_kref, dxgcontext_release);
+}
+
+void dxgcontext_destroy_safe(struct dxgprocess *process,
+			     struct dxgcontext *context)
+{
+	struct dxgdevice *device = context->device;
+
+	dxgdevice_acquire_context_list_lock(device);
+	dxgcontext_destroy(process, context);
+	dxgdevice_release_context_list_lock(device);
+}
+
+bool dxgcontext_is_active(struct dxgcontext *context)
+{
+	return context->object_state == DXGOBJECTSTATE_ACTIVE;
+}
+
+void dxgcontext_release(struct kref *refcount)
+{
+	struct dxgcontext *context;
+
+	context = container_of(refcount, struct dxgcontext, context_kref);
+	vfree(context);
+}
+
 struct dxgprocess_adapter *dxgprocess_adapter_create(struct dxgprocess *process,
 						     struct dxgadapter *adapter)
 {
diff --git a/drivers/hv/dxgkrnl/dxgkrnl.h b/drivers/hv/dxgkrnl/dxgkrnl.h
index e0a433c36a06..b4ca479cdd1a 100644
--- a/drivers/hv/dxgkrnl/dxgkrnl.h
+++ b/drivers/hv/dxgkrnl/dxgkrnl.h
@@ -30,6 +30,7 @@
 struct dxgprocess;
 struct dxgadapter;
 struct dxgdevice;
+struct dxgcontext;
 
 #include "misc.h"
 #include "hmgr.h"
@@ -281,6 +282,7 @@ void dxgadapter_remove_process(struct dxgprocess_adapter *process_info);
 /*
  * The object represent the device object.
  * The following objects take reference on the device
+ * - dxgcontext
  * - device handle (struct d3dkmthandle)
  */
 struct dxgdevice {
@@ -294,6 +296,8 @@ struct dxgdevice {
 	struct kref		device_kref;
 	/* Protects destcruction of the device object */
 	struct rw_semaphore	device_lock;
+	struct rw_semaphore	context_list_lock;
+	struct list_head	context_list_head;
 	/* List of paging queues. Protected by process handle table lock. */
 	struct list_head	pqueue_list_head;
 	struct d3dkmthandle	handle;
@@ -308,7 +312,33 @@ void dxgdevice_mark_destroyed(struct dxgdevice *device);
 int dxgdevice_acquire_lock_shared(struct dxgdevice *dev);
 void dxgdevice_release_lock_shared(struct dxgdevice *dev);
 void dxgdevice_release(struct kref *refcount);
+void dxgdevice_add_context(struct dxgdevice *dev, struct dxgcontext *ctx);
+void dxgdevice_remove_context(struct dxgdevice *dev, struct dxgcontext *ctx);
 bool dxgdevice_is_active(struct dxgdevice *dev);
+void dxgdevice_acquire_context_list_lock(struct dxgdevice *dev);
+void dxgdevice_release_context_list_lock(struct dxgdevice *dev);
+
+/*
+ * The object represent the execution context of a device.
+ */
+struct dxgcontext {
+	enum dxgobjectstate	object_state;
+	struct dxgdevice	*device;
+	struct dxgprocess	*process;
+	/* entry in the device context list */
+	struct list_head	context_list_entry;
+	struct list_head	hwqueue_list_head;
+	struct rw_semaphore	hwqueue_list_lock;
+	struct kref		context_kref;
+	struct d3dkmthandle	handle;
+	struct d3dkmthandle	device_handle;
+};
+
+struct dxgcontext *dxgcontext_create(struct dxgdevice *dev);
+void dxgcontext_destroy(struct dxgprocess *pr, struct dxgcontext *ctx);
+void dxgcontext_destroy_safe(struct dxgprocess *pr, struct dxgcontext *ctx);
+void dxgcontext_release(struct kref *refcount);
+bool dxgcontext_is_active(struct dxgcontext *ctx);
 
 void init_ioctls(void);
 long dxgk_compat_ioctl(struct file *f, unsigned int p1, unsigned long p2);
@@ -349,6 +379,14 @@ struct d3dkmthandle dxgvmb_send_create_device(struct dxgadapter *adapter,
 int dxgvmb_send_destroy_device(struct dxgadapter *adapter,
 			       struct dxgprocess *process,
 			       struct d3dkmthandle h);
+struct d3dkmthandle
+dxgvmb_send_create_context(struct dxgadapter *adapter,
+			   struct dxgprocess *process,
+			   struct d3dkmt_createcontextvirtual
+			   *args);
+int dxgvmb_send_destroy_context(struct dxgadapter *adapter,
+				struct dxgprocess *process,
+				struct d3dkmthandle h);
 int dxgvmb_send_query_adapter_info(struct dxgprocess *process,
 				   struct dxgadapter *adapter,
 				   struct d3dkmt_queryadapterinfo *args);
diff --git a/drivers/hv/dxgkrnl/dxgprocess.c b/drivers/hv/dxgkrnl/dxgprocess.c
index 734585689213..1e6500e12a22 100644
--- a/drivers/hv/dxgkrnl/dxgprocess.c
+++ b/drivers/hv/dxgkrnl/dxgprocess.c
@@ -258,6 +258,10 @@ struct dxgdevice *dxgprocess_device_by_object_handle(struct dxgprocess *process,
 		case HMGRENTRY_TYPE_DXGDEVICE:
 			device = obj;
 			break;
+		case HMGRENTRY_TYPE_DXGCONTEXT:
+			device_handle =
+			    ((struct dxgcontext *)obj)->device_handle;
+			break;
 		default:
 			pr_err("invalid handle type: %d\n", t);
 			break;
diff --git a/drivers/hv/dxgkrnl/dxgvmbus.c b/drivers/hv/dxgkrnl/dxgvmbus.c
index 5b560754ac0d..bfd09f98f82c 100644
--- a/drivers/hv/dxgkrnl/dxgvmbus.c
+++ b/drivers/hv/dxgkrnl/dxgvmbus.c
@@ -710,6 +710,105 @@ int dxgvmb_send_destroy_device(struct dxgadapter *adapter,
 	return ret;
 }
 
+struct d3dkmthandle
+dxgvmb_send_create_context(struct dxgadapter *adapter,
+			   struct dxgprocess *process,
+			   struct d3dkmt_createcontextvirtual *args)
+{
+	struct dxgkvmb_command_createcontextvirtual *command = NULL;
+	u32 cmd_size;
+	int ret;
+	struct d3dkmthandle context = {};
+	struct dxgvmbusmsg msg = {.hdr = NULL};
+
+	if (args->priv_drv_data_size > DXG_MAX_VM_BUS_PACKET_SIZE) {
+		pr_err("PrivateDriverDataSize is invalid");
+		ret = -EINVAL;
+		goto cleanup;
+	}
+	cmd_size = sizeof(struct dxgkvmb_command_createcontextvirtual) +
+	    args->priv_drv_data_size - 1;
+
+	ret = init_message(&msg, adapter, process, cmd_size);
+	if (ret)
+		goto cleanup;
+	command = (void *)msg.msg;
+
+	command_vgpu_to_host_init2(&command->hdr,
+				   DXGK_VMBCOMMAND_CREATECONTEXTVIRTUAL,
+				   process->host_handle);
+	command->device = args->device;
+	command->node_ordinal = args->node_ordinal;
+	command->engine_affinity = args->engine_affinity;
+	command->flags = args->flags;
+	command->client_hint = args->client_hint;
+	command->priv_drv_data_size = args->priv_drv_data_size;
+	if (args->priv_drv_data_size) {
+		ret = copy_from_user(command->priv_drv_data,
+				     args->priv_drv_data,
+				     args->priv_drv_data_size);
+		if (ret) {
+			pr_err("%s Faled to copy private data",
+				__func__);
+			ret = -EINVAL;
+			goto cleanup;
+		}
+	}
+	/* Input command is returned back as output */
+	ret = dxgvmb_send_sync_msg(msg.channel, msg.hdr, msg.size,
+				   command, cmd_size);
+	if (ret < 0) {
+		goto cleanup;
+	} else {
+		context = command->context;
+		if (args->priv_drv_data_size) {
+			ret = copy_to_user(args->priv_drv_data,
+					   command->priv_drv_data,
+					   args->priv_drv_data_size);
+			if (ret) {
+				pr_err("%s Faled to copy private data to user",
+					__func__);
+				ret = -EINVAL;
+				dxgvmb_send_destroy_context(adapter, process,
+							    context);
+				context.v = 0;
+			}
+		}
+	}
+
+cleanup:
+	free_message(&msg, process);
+	if (ret)
+		pr_debug("err: %s %d", __func__, ret);
+	return context;
+}
+
+int dxgvmb_send_destroy_context(struct dxgadapter *adapter,
+				struct dxgprocess *process,
+				struct d3dkmthandle h)
+{
+	int ret;
+	struct dxgkvmb_command_destroycontext *command;
+	struct dxgvmbusmsg msg = {.hdr = NULL};
+
+	ret = init_message(&msg, adapter, process, sizeof(*command));
+	if (ret)
+		goto cleanup;
+	command = (void *)msg.msg;
+
+	command_vgpu_to_host_init2(&command->hdr,
+				   DXGK_VMBCOMMAND_DESTROYCONTEXT,
+				   process->host_handle);
+	command->context = h;
+
+	ret = dxgvmb_send_sync_msg_ntstatus(msg.channel, msg.hdr, msg.size);
+cleanup:
+	free_message(&msg, process);
+	if (ret)
+		pr_debug("err: %s %d", __func__, ret);
+	return ret;
+}
+
 int dxgvmb_send_query_adapter_info(struct dxgprocess *process,
 				   struct dxgadapter *adapter,
 				   struct d3dkmt_queryadapterinfo *args)
diff --git a/drivers/hv/dxgkrnl/ioctl.c b/drivers/hv/dxgkrnl/ioctl.c
index a6be88b6c792..879fb3c6b7b2 100644
--- a/drivers/hv/dxgkrnl/ioctl.c
+++ b/drivers/hv/dxgkrnl/ioctl.c
@@ -567,6 +567,174 @@ dxgk_destroy_device(struct dxgprocess *process, void *__user inargs)
 	return ret;
 }
 
+static int
+dxgk_create_context_virtual(struct dxgprocess *process, void *__user inargs)
+{
+	struct d3dkmt_createcontextvirtual args;
+	int ret;
+	struct dxgadapter *adapter = NULL;
+	struct dxgdevice *device = NULL;
+	struct dxgcontext *context = NULL;
+	struct d3dkmthandle host_context_handle = {};
+	bool device_lock_acquired = false;
+
+	pr_debug("ioctl: %s", __func__);
+
+	ret = copy_from_user(&args, inargs, sizeof(args));
+	if (ret) {
+		pr_err("%s failed to copy input args", __func__);
+		ret = -EINVAL;
+		goto cleanup;
+	}
+
+	/*
+	 * The call acquires reference on the device. It is safe to access the
+	 * adapter, because the device holds reference on it.
+	 */
+	device = dxgprocess_device_by_handle(process, args.device);
+	if (device == NULL) {
+		ret = -EINVAL;
+		goto cleanup;
+	}
+
+	ret = dxgdevice_acquire_lock_shared(device);
+	if (ret < 0)
+		goto cleanup;
+
+	device_lock_acquired = true;
+
+	adapter = device->adapter;
+	ret = dxgadapter_acquire_lock_shared(adapter);
+	if (ret < 0) {
+		adapter = NULL;
+		goto cleanup;
+	}
+
+	context = dxgcontext_create(device);
+	if (context == NULL) {
+		ret = -ENOMEM;
+		goto cleanup;
+	}
+
+	host_context_handle = dxgvmb_send_create_context(adapter,
+							 process, &args);
+	if (host_context_handle.v) {
+		hmgrtable_lock(&process->handle_table, DXGLOCK_EXCL);
+		ret = hmgrtable_assign_handle(&process->handle_table, context,
+					      HMGRENTRY_TYPE_DXGCONTEXT,
+					      host_context_handle);
+		if (ret >= 0)
+			context->handle = host_context_handle;
+		hmgrtable_unlock(&process->handle_table, DXGLOCK_EXCL);
+		if (ret < 0)
+			goto cleanup;
+		ret = copy_to_user(&((struct d3dkmt_createcontextvirtual *)
+				   inargs)->context, &host_context_handle,
+				   sizeof(struct d3dkmthandle));
+		if (ret) {
+			pr_err("%s failed to copy context handle", __func__);
+			ret = -EINVAL;
+		}
+	} else {
+		pr_err("invalid host handle");
+		ret = -EINVAL;
+	}
+
+cleanup:
+
+	if (ret < 0) {
+		if (host_context_handle.v) {
+			dxgvmb_send_destroy_context(adapter, process,
+						    host_context_handle);
+		}
+		if (context)
+			dxgcontext_destroy_safe(process, context);
+	}
+
+	if (adapter)
+		dxgadapter_release_lock_shared(adapter);
+
+	if (device) {
+		if (device_lock_acquired)
+			dxgdevice_release_lock_shared(device);
+		kref_put(&device->device_kref, dxgdevice_release);
+	}
+
+	pr_debug("ioctl:%s %s %d", errorstr(ret), __func__, ret);
+	return ret;
+}
+
+static int
+dxgk_destroy_context(struct dxgprocess *process, void *__user inargs)
+{
+	struct d3dkmt_destroycontext args;
+	int ret;
+	struct dxgadapter *adapter = NULL;
+	struct dxgcontext *context = NULL;
+	struct dxgdevice *device = NULL;
+	struct d3dkmthandle device_handle = {};
+
+	pr_debug("ioctl: %s", __func__);
+
+	ret = copy_from_user(&args, inargs, sizeof(args));
+	if (ret) {
+		pr_err("%s failed to copy input args", __func__);
+		ret = -EINVAL;
+		goto cleanup;
+	}
+
+	hmgrtable_lock(&process->handle_table, DXGLOCK_EXCL);
+	context = hmgrtable_get_object_by_type(&process->handle_table,
+					       HMGRENTRY_TYPE_DXGCONTEXT,
+					       args.context);
+	if (context) {
+		hmgrtable_free_handle(&process->handle_table,
+				      HMGRENTRY_TYPE_DXGCONTEXT, args.context);
+		context->handle.v = 0;
+		device_handle = context->device_handle;
+		context->object_state = DXGOBJECTSTATE_DESTROYED;
+	}
+	hmgrtable_unlock(&process->handle_table, DXGLOCK_EXCL);
+
+	if (context == NULL) {
+		pr_err("invalid context handle: %x", args.context.v);
+		ret = -EINVAL;
+		goto cleanup;
+	}
+
+	/*
+	 * The call acquires reference on the device. It is safe to access the
+	 * adapter, because the device holds reference on it.
+	 */
+	device = dxgprocess_device_by_handle(process, device_handle);
+	if (device == NULL) {
+		ret = -EINVAL;
+		goto cleanup;
+	}
+
+	adapter = device->adapter;
+	ret = dxgadapter_acquire_lock_shared(adapter);
+	if (ret < 0) {
+		adapter = NULL;
+		goto cleanup;
+	}
+
+	ret = dxgvmb_send_destroy_context(adapter, process, args.context);
+
+	dxgcontext_destroy_safe(process, context);
+
+cleanup:
+
+	if (adapter)
+		dxgadapter_release_lock_shared(adapter);
+
+	if (device)
+		kref_put(&device->device_kref, dxgdevice_release);
+
+	pr_debug("ioctl:%s %s %d", errorstr(ret), __func__, ret);
+	return ret;
+}
+
 /*
  * IOCTL processing
  * The driver IOCTLs return
@@ -627,6 +795,10 @@ void init_ioctls(void)
 		  LX_DXOPENADAPTERFROMLUID);
 	SET_IOCTL(/*0x2 */ dxgk_create_device,
 		  LX_DXCREATEDEVICE);
+	SET_IOCTL(/*0x4 */ dxgk_create_context_virtual,
+		  LX_DXCREATECONTEXTVIRTUAL);
+	SET_IOCTL(/*0x5 */ dxgk_destroy_context,
+		  LX_DXDESTROYCONTEXT);
 	SET_IOCTL(/*0x9 */ dxgk_query_adapter_info,
 		  LX_DXQUERYADAPTERINFO);
 	SET_IOCTL(/*0x14 */ dxgk_enum_adapters,
diff --git a/drivers/hv/dxgkrnl/misc.h b/drivers/hv/dxgkrnl/misc.h
index 8948f48ec9dc..8f7b37049308 100644
--- a/drivers/hv/dxgkrnl/misc.h
+++ b/drivers/hv/dxgkrnl/misc.h
@@ -30,6 +30,7 @@ extern const struct d3dkmthandle zerohandle;
  * fd_mutex
  * plistmutex
  * table_lock
+ * context_list_lock
  * core_lock
  * device_lock
  * process_adapter_mutex
-- 
2.35.1